A whisky tax should be introduced in an independent Scotland, according to a new paper warning that income tax rises would also be needed to tackle austerity.

An analysis of the SNP’s indep­endence blueprint also suggests reducing Scottish university degrees from their traditional four-year term to save money, cutting defence spending and introducing a fee for basic health care.

The whisky industry has warned that any additional tax in an independent Scotland would threaten jobs and investment. Picture: Neil Hanna

The critique of Andrew Wilson’s Growth Commission was conducted by the economist John McLaren of the Scottish Trends website.

Professor McLaren also said the Growth Commission ignored the impact that rising health needs would have on unprotected budgets. He calculated that unprotected budgets would have to be cut by 15 per cent in order to meet the demand for health care.

In order to avoid the “austerity” he claimed would result from Mr Wilson’s blueprint, Professor McLaren made a series of recommendations. Among them were a whisky tax, which he said could prove attractive because manufacturers would not be able to move production elsewhere if they still wanted to call it Scotch. Last night his suggestion was resisted by the whisky industry, which said it would threaten jobs and investment.

Professor McLaren criticised the Growth Commission for a lack of transparency over the implications of spending restrictions. He said there was “no analysis” of the negative implications of breaking up the UK free trade area and a lack of clarity over Scotland’s debt position.

He also said there was an over- optimistic approach to start- up costs and the assignment of UK assets. Professor McLaren said: “It is difficult to see how another decade of austerity, involving real terms cuts in around the half budget, can be achieved. As a result, upfront savings need to be made rather than relying on an extended period of change which simply delays and prolongs the necessary fiscal adjustment.”

Keith Brown, depute leader of the SNP, said: “The Sustainable Growth Commission’s report has given us all hope for an alternative to the Tory chaos over Brexit, and has sparked positive discussions about how we can grow our economy, end austerity and build a fairer society as an independent country.

“The SNP approach will be to continue to reject austerity, and our focus will be to grow the economy and invest in Scotland’s future.”

A Scotch Whisky Association spokesman said: “Any additional tax, either on whisky or on tourism, would threaten jobs and investment.”